Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, a nacelle, one or more rotor blades, a gearbox, a generator, and a power converter. The rotor blades capture and transmit kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gearbox, or if a gearbox is not used, directly to the generator. The gearbox steps up the inherently low rotational speed of the rotor for the generator to efficiently convert the rotational mechanical energy to electrical energy, which is fed into a utility grid via at least one electrical connection. A power converter or bridge is typically used to convert a frequency of a generated electric power to a frequency substantially similar to a utility grid frequency. Conventional wind turbines also typically include a main controller to control various operational modes of the wind turbine.
Various wind turbines also include a converter controller configured to control the power converter. More specifically, the converter controller may be communicatively coupled to the power converter via a bridge logic interface. The bridge logic is a programmable logic device that generally refers to the quasi-intelligent Field-Programmable Gate Array (FPGA). In other words, the bridge logic is the program that is carried in the controller code and downloaded to the power bridge interface card at power-up of the wind turbine. In addition, the bridge logic typically interfaces with the converter controller over a serial link, e.g. a High-Speed Serial Link (HSSL), and the power bridge via discrete signals.
Typically, the communications between the controller and the bridge logic occurs periodically at regular intervals, generally referred to as a “frame.” For example, feedback communications are sent from the bridge logic to the controller at the beginning of each frame, and upon receipt of the feedback communications, the controller performs calculations that result in new command communications for the bridge logic for the next frame. The controller then sends the new command communications to the bridge logic before the start of the next frame. Upon receipt, the bridge logic uses information in the new command communications to configure the gating and feedback logic for the next frame.
Due to the number of asynchronous processes running in the controller, however, the bridge logic may not receive the new command communications in a timely fashion. Further, noise in the transmission of the new command communications and/or the feedback communications may delay the communications from being transmitted or received on time. Thus, the gating and feedback logic for the next frame may not be configured properly. For these and other reasons, the bridge logic may experience a resulting disturbance to its gating/command operations and fail to acquire and transmit feedback communications to the controller. Still further electrical components of the wind turbine may experience similar issues when communicating with the controller.
Accordingly, a system and method that addresses the aforementioned problems would be welcomed in the technology. More specifically, a system and method that incorporates contingency communications for the upcoming gating frame and one or more subsequent frames would be advantageous.